21个测试点没过

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int n, m;
int c[maxn], r[maxn], d[maxn], s[maxn], t[maxn], a[maxn];
bool bo(int x){
	memset(c, 0, sizeof(c));
	a[0] = 0;
	for(int i = 1;i <= x;i++){
		c[s[i]] += d[i];
		c[t[i] + 1] -= d[i];
	}for(int i = 1;i <= n;i++){
		a[i] = a[i - 1] + c[i];
		if(a[i] > r[i])return false;
	}return true;
}
int main(){
	scanf("%d%d", &n, &m);
	for(int i = 1;i <= n;i++){
		scanf("%d", &r[i]);
	}for(int i = 1;i <= m;i++){
		scanf("%d%d%d", &d[i], &s[i], &t[i]); 
	}int l = 1, end = m, ans = -1;
	while(l <= end){
		int mid = (l + end) / 2;
		if(bo(mid)) l = mid + 1;
		else {
			end = mid - 1;
			ans = mid;
		}
	}if(ans == -1){
		cout << 0;
		return 0;
	}cout << "-1" << endl << ans;
	return 0;
}